1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * PTP 1588 clock support - private declarations for the core module.
4 *
5 * Copyright (C) 2010 OMICRON electronics GmbH
6 */
7 #ifndef _PTP_PRIVATE_H_
8 #define _PTP_PRIVATE_H_
9
10 #include <linux/cdev.h>
11 #include <linux/device.h>
12 #include <linux/kthread.h>
13 #include <linux/mutex.h>
14 #include <linux/posix-clock.h>
15 #include <linux/ptp_clock.h>
16 #include <linux/ptp_clock_kernel.h>
17 #include <linux/time.h>
18 #include <linux/list.h>
19 #include <linux/bitmap.h>
20 #include <linux/debugfs.h>
21
22 #define PTP_MAX_TIMESTAMPS 128
23 #define PTP_BUF_TIMESTAMPS 30
24 #define PTP_DEFAULT_MAX_VCLOCKS 20
25 #define PTP_MAX_CHANNELS 2048
26
27 struct timestamp_event_queue {
28 struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
29 int head;
30 int tail;
31 spinlock_t lock;
32 struct list_head qlist;
33 unsigned long *mask;
34 struct dentry *debugfs_instance;
35 struct debugfs_u32_array dfs_bitmap;
36 };
37
38 struct ptp_clock {
39 struct posix_clock clock;
40 struct device dev;
41 struct ptp_clock_info *info;
42 dev_t devid;
43 int index; /* index into clocks.map */
44 struct pps_device *pps_source;
45 long dialed_frequency; /* remembers the frequency adjustment */
46 struct list_head tsevqs; /* timestamp fifo list */
47 spinlock_t tsevqs_lock; /* protects tsevqs from concurrent access */
48 struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
49 wait_queue_head_t tsev_wq;
50 int defunct; /* tells readers to go away when clock is being removed */
51 struct device_attribute *pin_dev_attr;
52 struct attribute **pin_attr;
53 struct attribute_group pin_attr_group;
54 /* 1st entry is a pointer to the real group, 2nd is NULL terminator */
55 const struct attribute_group *pin_attr_groups[2];
56 struct kthread_worker *kworker;
57 struct kthread_delayed_work aux_work;
58 unsigned int max_vclocks;
59 unsigned int n_vclocks;
60 int *vclock_index;
61 struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */
62 bool is_virtual_clock;
63 bool has_cycles;
64 struct dentry *debugfs_root;
65 };
66
67 #define info_to_vclock(d) container_of((d), struct ptp_vclock, info)
68 #define cc_to_vclock(d) container_of((d), struct ptp_vclock, cc)
69 #define dw_to_vclock(d) container_of((d), struct ptp_vclock, refresh_work)
70
71 struct ptp_vclock {
72 struct ptp_clock *pclock;
73 struct ptp_clock_info info;
74 struct ptp_clock *clock;
75 struct hlist_node vclock_hash_node;
76 struct cyclecounter cc;
77 struct timecounter tc;
78 struct mutex lock; /* protects tc/cc */
79 };
80
81 /*
82 * The function queue_cnt() is safe for readers to call without
83 * holding q->lock. Readers use this function to verify that the queue
84 * is nonempty before proceeding with a dequeue operation. The fact
85 * that a writer might concurrently increment the tail does not
86 * matter, since the queue remains nonempty nonetheless.
87 */
queue_cnt(const struct timestamp_event_queue * q)88 static inline int queue_cnt(const struct timestamp_event_queue *q)
89 {
90 /*
91 * Paired with WRITE_ONCE() in enqueue_external_timestamp(),
92 * ptp_read(), extts_fifo_show().
93 */
94 int cnt = READ_ONCE(q->tail) - READ_ONCE(q->head);
95 return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
96 }
97
98 /* Check if ptp virtual clock is in use */
ptp_vclock_in_use(struct ptp_clock * ptp)99 static inline bool ptp_vclock_in_use(struct ptp_clock *ptp)
100 {
101 bool in_use = false;
102
103 if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
104 return true;
105
106 if (!ptp->is_virtual_clock && ptp->n_vclocks)
107 in_use = true;
108
109 mutex_unlock(&ptp->n_vclocks_mux);
110
111 return in_use;
112 }
113
114 /* Check if ptp clock shall be free running */
ptp_clock_freerun(struct ptp_clock * ptp)115 static inline bool ptp_clock_freerun(struct ptp_clock *ptp)
116 {
117 if (ptp->has_cycles)
118 return false;
119
120 return ptp_vclock_in_use(ptp);
121 }
122
123 extern const struct class ptp_class;
124
125 /*
126 * see ptp_chardev.c
127 */
128
129 /* caller must hold pincfg_mux */
130 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
131 enum ptp_pin_function func, unsigned int chan);
132
133 long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
134 unsigned long arg);
135
136 int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode);
137
138 int ptp_release(struct posix_clock_context *pccontext);
139
140 ssize_t ptp_read(struct posix_clock_context *pccontext, uint flags, char __user *buf,
141 size_t cnt);
142
143 __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
144 poll_table *wait);
145
146 /*
147 * see ptp_sysfs.c
148 */
149
150 extern const struct attribute_group *ptp_groups[];
151
152 int ptp_populate_pin_groups(struct ptp_clock *ptp);
153 void ptp_cleanup_pin_groups(struct ptp_clock *ptp);
154
155 struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock);
156 void ptp_vclock_unregister(struct ptp_vclock *vclock);
157 #endif
158